1. Field of the Invention
The present invention relates to a vibration attenuating technique for an electronic component used in an electronic apparatus, such as a personal computer or a projector and, more particularly, to a damper which attenuates a vibration generated by the electronic component to make it hard for the vibration to be transmitted to the casing of an electronic apparatus, and to an electronic component and an electronic apparatus that are equipped with such a damper.
2. Description of the Related Art
An electronic component generating vibration is mounted in an electronic apparatus such as a personal computer or a projector. For example, an electronic component such as a cooling fan or a disk device is equipped with a motor for a rotary drive member; when the motor rotates, a vibration is generated. When this vibration is transmitted to the casing of the electronic apparatus, the electronic apparatus as a whole vibrates, and there is a fear of noise being generated and a fear of failure of the electronic apparatus being incurred.
In view of this, to make it hard for a vibration generated by an electronic component to be transmitted to the casing of an electronic apparatus, JP 09-270975 A, for example, discloses a structure in which a cooling fan is fixed to a casing by screws, with a ring-like vibration-proof rubber member being held between the cooling fan and the casing. Further, JP 2000-27799 A discloses a structure in which a cylindrical rubber bush mounted to a cooling fan mounting portion is mounted to a casing by screws.
Further, there also exists a damper 3 which needs no fixation by screws. As shown in FIGS. 28A through 28C, the damper 3 is equipped with a disc portion 1 and a mounting insertion portion 2 protruding from the center of the plate surface of the disc portion 1; as shown in FIG. 29, the mounting insertion portion 2 of the damper 3 is inserted into a mounting hole 4a of a cooling fan 4, and the cooling fan 4 is elastically supported and fixed to a casing 5, with the disc portion 1 abutting the casing 5.
While in the ring-like vibration-proof rubber member disclosed in JP 09-270975 A it is possible to attenuate a vibration in the axial direction of the screws, a sufficient attenuation effect cannot be exerted with respect to a vibration in a direction perpendicular to the axis; further, the fixation is effected by screws, so the operation of mounting the cooling fan is a bother. The cylindrical rubber bush as disclosed in JP 2000-27799 A is capable of attenuating vibration in different directions; however, as in the case of JP 09-270975 A, due to the fixation by screws, the operation of mounting the cooling fan is a bother. Further, in the damper 3 as shown in FIGS. 28A through 28C, using a flexible material of high vibration attenuation property may result in deformation of the mounting insertion portion 2 as shown in FIG. 29, making it impossible for the mounting insertion portion 2 to be reliably inserted into the mounting hole 4a of the cooling fan 4; if the cooling fan 4 is fixed to the casing 5 in this state, a sufficient attenuation effect is not to be expected.